Definition of phenanthroline
: any of three crystalline nitrogen bases C12H8N2 related to phenanthrene and derivable from ortho-, meta-, and para-phenylenediamine; di-aza-phenanthrene; especially : the ortho or 1,10-isomer that forms a red coordination complex with ferrous ions useful as an oxidation-reduction indicator (as with potassium permanganate as oxidizing agent) because it becomes faint blue in the oxidized form
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Origin and Etymology of phenanthroline
International Scientific Vocabulary phenanthr- + quinoline
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